Aggressive papillary middle-ear tumor. A clinicopathologic entity distinct from middle-ear adenoma

A 29-year-old woman had a middle-ear mass that resulted in hearing loss and seventh-nerve palsy. The tumor invaded the petrous bone, the mastoid, at least one semicircular canal, and then extended into the posterior fossa. Microscopically, it consisted of complex, interdigitating papillae lined by uniform, cuboidal to low columnar cells. The cells resembled the epithelium of the normal middle ear and middle-ear adenoma, but the papillary architecture distinguished this neoplasm from the latter, nonpapillary tumors. Papillary middle-ear tumors are locally invasive. We propose the term "aggressive papillary middle-ear tumor" (APMET). Nine other examples of APMET have been reported under various diagnostic terms. All have been locally destructive with frequent intracranial invasion. Although none of the tumors has metastasized, one patient died of uncontrolled local disease. For this reason, APMET must be distinguished from nonpapillary middle-ear tumors.     

Soft-tissue myoepithelioma of the hypothenar region: a case report

Myoepithelial tumors only recently have been recognized as occurring primarily in soft tissue, and only a few cases have been described in the literature. The occurrence of these tumors in the hand is even more limited. In this article, we review the clinical, radiologic, and histologic features of a benign myoepithelioma of the hypothenar region of the left hand.     

Malignant myoepithelioma of cranial dura

Malignant tumors of myoepithelial origin have been increasingly recognized at a variety of sites. Herein, we describe an example of malignant myoepithelioma arising in intracranial dura. The patient is a 47-year-old woman who presented with intracranial hemorrhage and on magnetic resonance imaging was found to have an enhancing tumor. No extracranial primary tumor was identified. A gross total resection was performed. Histologically, it varied in pattern from diffuse to focally (<10%) ductular and consisted of epitheloid to spindle cells showing marked mitotic activity. Prominent infiltration of the dura was noted. Immunohistochemical stains showed convincing expression of cytokeratins (AE1/AE3 and CAM 5.2), S-100 protein, smooth muscle actin, and glial fibrillary acidic protein. Electron microscopy performed on formalin-fixed, paraffin-embedded tissue demonstrated cohesive cells with focal intermediate filament content and surface basal lamina formation at stromal interfaces. Occasional desmosomes with tonofilaments surrounded intercellular lumina containing masses of filamentous material. This example of malignant myoepithelioma is the first convincing primary salivary gland type tumor to arise in an intracranial location outside the sellar region or ear. Intracranial dura should be added to various sites at which this morphologically heterogenous tumor may arise.     

Metastatic myoepithelioma of the breast

Myoepitheliomas are typically benign tumours arising from exocrine glands. There have only been five reports of malignant myoepitheliomas from breast origin previously published in the English literature. This report describes a patient with myoepithelioma arising in the breast which later metastasized despite the primary tumour having benign histological features. Impaired immune function due to end-stage renal failure and haemodialysis may have contributed to the malignant potential of her tumour. The literature regarding myoepithelial tumours is reviewed. All breast myoepitheliomas should be managed as potentially malignant tumours with appropriate surgical clearance and staging.     

Plasmacytoid myoepithelioma of minor salivary glands: report of case with emphasis in the immunohistochemical findings

Extracorporeal formation of mineralized bone-like tissue is still an unsolved challenge in tissue engineering. Embryonic stem cells may open up new therapeutic options for the future and should be an interesting model for the analysis of fetal organogenesis. Here we describe a technique for culturing embryonic stem cells (ESCs) in the absence of artificial scaffolds which generated mineralized miromasses. Embryonic stem cells were harvested and osteogenic differentiation was stimulated by the addition of dexamethasone, ascorbic acid, and ß-glycerolphosphate (DAG). After three days of cultivation microspheres were formed. These spherical three-dimensional cell units showed a peripheral zone consisting of densely packed cell layers surrounded by minerals that were embedded in the extracellular matrix. Alizarine red staining confirmed evidence of mineralization after 10 days of DAG stimulation in the stimulated but not in the control group. Transmission electron microscopy demonstrated scorching crystallites and collagenous fibrils as early indication of bone formation. These extracellular structures resembled hydroxyl apatite-like crystals as demonstrated by distinct diffraction patterns using electron diffraction analysis. The micromass culture technique is an appropriate model to form three-dimensional bone-like micro-units without the need for an underlying scaffold. Further studies will have to show whether the technique is applicable also to pluripotent stem cells of different origin.     

Chronic intussusception due to antral myoepithelioma

Intussusception was seen on abdominal sonography and computed tomography in a 15-year-old boy who presented with a 6-week history of weight loss, vomiting, abdominal pain, abdominal mass, and hyperamylasemia. Laparotomy revealed a chronic gastroduodenal intussusception, the lead point of which was an antral myoepithelioma, a rare entity in this age group.     

Glycogen-rich clear cell mammary malignant myoepithelioma

Primary clear cell tumors of the breast are uncommon and often present a diagnostic challenge. We describe an extremely rare case of glycogen-rich clear cell malignant myoepithelioma in a 43-year-old woman. Histologically, this tumor is composed of clear cells with abundant cytoplasmic glycogen particles. Immunohistochemically, these tumor cells show co-expression of vimentin, smooth muscle actin, epithelial membrane antigen, S-100 protein, and cytokeratin as evidence of myoepithelial cell tumor. The pathological staging of the patient is IIB (pT3N0M0) and the nuclear grading is 2. The patient demonstrated no evidence of recurrence or metastasis over a period of 42 months. We suggest that glycogen-rich clear cell malignant myoepithelioma be included in the histological differential diagnosis of clear cell tumors of the breast.     

Intraductal growth of malignant mammary myoepithelioma.

This report describes the histologic and immunohistologic features of an intraductal myoepithelial tumor that developed in the breast of a 61-year-old woman. Histologically, the tumor proliferated intraductally, with both a comedo or doughnut pattern and a solid pattern containing narrow fibrovascular cores, mimicking what appeared to be a conventional intraductal carcinoma. No fine papillary or arborizing growth or cribriform formation was observed. Tumor cells at the ductal peripheral zone were polygonal and clear with abundant glycogen in the cytoplasm; they were transformed into nonclear cells with slightly eosinophilic cytoplasm toward the center of the involved ducts. Occasionally, nonclear cells were elongated, with a centrally located cigar-shaped nucleus. These elongated or spindle cells tended to show a fascicular and streaming pattern similar to that of a smooth muscle tumor. Immunohistochemically, alpha smooth muscle actin (alpha-SM-actin) and S-100 protein were expressed in most of the nonclear cells. While clear cells also had a positive reaction for S-100 protein, they were mostly negative or barely positive for alpha-SM-actin. Epithelial membrane antigen (EMA) was also positive in a certain number of polygonal cells. These results support the myoepithelial nature of the present tumor, and some cells might also be immunologically differentiated into ductal epithelial cells. In addition to cytological atypia, frequent mitoses, and central necrosis within ducts, there was a minimal but evident stromal invasion, suggesting histological malignancy in this peculiar tumor.     

Soft tissue myoepithelioma of the ring finger of the right hand with intraosseous extension: a case report

Myoepithelial soft tissue tumors represent less than 1% of soft tissue tumors. Diagnosis is based on histology, but clinical and radiological features can orient the practitioner. Myoepithelial tumors do not involve the bone as they are not malignant. In this article, we report a case of a myoepithelioma occuring on the volar aspect of the right ring finger involving the first phalanx.     

Spindle cell myoepithelioma of the nasal cavity.

Minor salivary gland neoplasms with mesenchymal-like features are uncommon in the sinonasal tract. We herein report a case of spindle cell myoepithelioma of the nasal cavity in a 69-year-old woman who presented with a rapidly expanding tumor accompanied by episodes of epistaxis. Although initially considered as a mesenchymal neoplasm, ultrastructural and immunophenotypical characterization demonstrated its myoepithelial nature. In the sinonasal setting, this unusual neoplasm may be confused with soft tissue tumors showing spindle cell or myxoid features. Staining for cytokeratin is found to be the most useful adjunct to diagnosis.     

Tympanometry for middle-ear effusion in unconscious ICU patients.

Eighty-six bilateral impedance audiometries were performed weekly in 35 unconscious ICU patients. Tympanometry showed the presence of middle-ear effusion in 43.3% of the examinations (80% of the patients). The incidence of effusion was significantly higher in patients older than 50 years, in intubated and mechanically ventilated patients and in the presence of microbial colonization of the upper airways. The acoustic reflex (AR) was characterized by increased threshold values in 23.8% of the examinations and was absent in 41.3%. Abnormal or absent ARs were usually associated with middle-ear effusion or tube malfunction.     

Lack of efficacy of middle-ear inflation: treatment of otitis media with effusion in children

A randomized controlled trial was conducted to evaluate the efficacy of autoinflation of the middle ear in the treatment of otitis media with effusion. Forty-one children with middle ear effusion not responsive to antimicrobial therapy enrolled in the study. Of these subjects, 75 percent had effusion duration over 3 months. A system consisting of a disposable anesthesia mask attached to a flowmeter was used to teach children to perform autoinflation based on a modified Valsalva technique. Subjects were stratified according to their ability to achieve tubal opening as assessed by tympanometry and tubosonometry. Subjects were randomly assigned to either treatment or observation group and were followed weekly for 2 weeks; subjects in the treatment group attempted inflation three times each day for 2 weeks. Of the 19 subjects who were in the autoinflation group, only one (5.3 percent) was effusion-free at the two-week endpoint and of the 21 subjects in the control, only two (9.5 percent) were without middle-ear effusion. Autoinflation was ineffective for treatment of children with otitis media with effusion in our study.     

Granisetron in the prevention of nausea and vomiting after middle-ear surgery: a dose-ranging study

This study was undertaken to determine the minimum effective dose of granisetron, a selective 5-hydroxytryptamine type 3 receptor antagonist, for the prevention of postoperative nausea and vomiting (PONV) after middle-ear surgery. In a randomized, double-blind, placebo- controlled trial, 120 women (ASA I) received placebo (saline) or granisetron at three different doses (20 micrograms kg-1, 40 micrograms kg-1, 100 micrograms kg-1) i.v. immediately before the induction of anaesthesia (n = 30 for each group). A standard general anaesthetic technique was used throughout. A complete response, defined as no PONV and no need for another rescue antiemetic during 0-3 h after anaesthesia, occurred in 40%, 43%, 83% and 87% of patients who had received placebo, granisetron 20 micrograms kg-1, granisetron 40 micrograms kg-1 or granisetron 100 micrograms kg-1, respectively; the corresponding incidence during 3-21 h after anaesthesia was 47%, 47%, 87% and 87% (P < 0.05; overall Fisher's exact probability test). Granisetron 40 micrograms kg-1 appears to be the minimum effective dose for preventing PONV in women undergoing middle-ear surgery.